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    (adsbygoogle = window.adsbygoogle || []).push({});
    </script></div> <p>兼容性：Dart Sass ✓ <span class="sa-ver-divider">|</span>LibSass  ✗<span class="sa-ver-divider">|</span>Ruby Sass  <span class="badge tip" style="vertical-align:middle;" data-v-0f036736>4.0.0(unreleased)</span></p> <blockquote><p>LibSass和旧版本的Ruby Sass认为没有单元的数字与带任意单位的数字相等。这种行为已经被弃用，并且在最近的版本中被删除了，因为它违反了<a href="https://zh.wikipedia.org/wiki/%E4%BC%A0%E9%80%92%E5%85%B3%E7%B3%BB" target="_blank" rel="noopener noreferrer">传递性<svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" x="0px" y="0px" viewBox="0 0 100 100" width="15" height="15" class="icon outbound"><path fill="currentColor" d="M18.8,85.1h56l0,0c2.2,0,4-1.8,4-4v-32h-8v28h-48v-48h28v-8h-32l0,0c-2.2,0-4,1.8-4,4v56C14.8,83.3,16.6,85.1,18.8,85.1z"></path> <polygon fill="currentColor" points="45.7,48.7 51.3,54.3 77.2,28.5 77.2,37.2 85.2,37.2 85.2,14.9 62.8,14.9 62.8,22.9 71.5,22.9"></polygon></svg></a>。</p></blockquote> <p>等值运算符返回两个值是否相同。<code>&lt;expression&gt; == &lt;expression&gt;</code>，返回两个<a href="/sass-cn/api/Syntax/Structure.html#表达式">表达式</a>是否相等；<code>&lt;expression&gt; != &lt;expression&gt;</code>，返回两个表达式是否不相等。如果两个值是相同的类型和相同的值，则认为它们是相等的，这意味着不同的类型有不同的含义：</p> <ul><li><a href="/sass-cn/api/Values/Numbers.html">Numbers</a>，如果具有相同的值和相同的单位，或者当它们的单位相互转换时，它们的值是相等的，那么它们就是相等的。</li> <li><a href="/sass-cn/api/Values/Strings.html">Srings</a>，相同内容的<a href="/sass-cn/api/Values/Strings.html#不带引号的字符串">不带引用的字符串</a>和<a href="/sass-cn/api/Values/Strings.html#带引号的字符串">带引用的字符串</a>被认为是相等的。</li> <li><a href="/sass-cn/api/Values/Colors.html">Colors</a>，如果它们具有相同的红、绿、蓝和alpha值，则视为是相等的。</li> <li><a href="/sass-cn/api/Values/Lists.html">Lists</a>，如果列表的内容是相同的，则列表也是相等的。逗号分隔的列表不等于空格分隔的列表，带括号的列表也不等于不带括号的列表。</li> <li><a href="/sass-cn/api/Values/Maps.html">Maps</a>，如果键和值都相等，就是相等的。</li> <li><a href="/sass-cn/api/Values/Booleans.html">true、false</a>和<a href="/sass-cn/api/Values/Null.html">null</a>只等于它们自己。</li> <li><a href="/sass-cn/api/Values/Functions.html">Functions</a>。函数是通过引用进行比较的，因此即使两个函数具有相同的名称和定义，如果不在相同的位置定义，它们也会被认为是不同的。</li></ul> <div class="el-tabs el-tabs--top el-tabs--border-card"><div class="el-tabs__header is-top"><div class="el-tabs__nav-wrap is-top"><div class="el-tabs__nav-scroll"><div role="tablist" class="el-tabs__nav is-top" style="transform:translateX(-0px);"></div></div></div></div><div class="el-tabs__content"><div role="tabpanel" aria-hidden="true" id="pane-null" aria-labelledby="tab-null" class="el-tab-pane" style="display:none;"><div class="language-scss extra-class"><pre class="language-scss"><code><span class="token keyword">@debug</span> 1px <span class="token operator">==</span> 1px<span class="token punctuation">;</span> <span class="token comment">// true</span>
<span class="token keyword">@debug</span> 1px <span class="token operator">!=</span> 1em<span class="token punctuation">;</span> <span class="token comment">// true</span>
<span class="token keyword">@debug</span> 1 <span class="token operator">!=</span> 1px<span class="token punctuation">;</span> <span class="token comment">// true</span>
<span class="token keyword">@debug</span> 96px <span class="token operator">==</span> 1in<span class="token punctuation">;</span> <span class="token comment">// true</span>

<span class="token keyword">@debug</span> <span class="token string">&quot;Helvetica&quot;</span> <span class="token operator">==</span> Helvetica<span class="token punctuation">;</span> <span class="token comment">// true</span>
<span class="token keyword">@debug</span> <span class="token string">&quot;Helvetica&quot;</span> <span class="token operator">!=</span> <span class="token string">&quot;Arial&quot;</span><span class="token punctuation">;</span> <span class="token comment">// true</span>

<span class="token keyword">@debug</span> <span class="token function">hsl</span><span class="token punctuation">(</span>34<span class="token punctuation">,</span> 35%<span class="token punctuation">,</span> 92.1%<span class="token punctuation">)</span> <span class="token operator">==</span> #f2ece4<span class="token punctuation">;</span> <span class="token comment">// true</span>
<span class="token keyword">@debug</span> <span class="token function">rgba</span><span class="token punctuation">(</span>179<span class="token punctuation">,</span> 115<span class="token punctuation">,</span> 153<span class="token punctuation">,</span> 0.5<span class="token punctuation">)</span> <span class="token operator">!=</span> <span class="token function">rgba</span><span class="token punctuation">(</span>179<span class="token punctuation">,</span> 115<span class="token punctuation">,</span> 153<span class="token punctuation">,</span> 0.8<span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token comment">// true</span>

<span class="token keyword">@debug</span> <span class="token punctuation">(</span>5px 7px 10px<span class="token punctuation">)</span> <span class="token operator">==</span> <span class="token punctuation">(</span>5px 7px 10px<span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token comment">// true</span>
<span class="token keyword">@debug</span> <span class="token punctuation">(</span>5px 7px 10px<span class="token punctuation">)</span> <span class="token operator">!=</span> <span class="token punctuation">(</span>10px 14px 20px<span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token comment">// true</span>
<span class="token keyword">@debug</span> <span class="token punctuation">(</span>5px 7px 10px<span class="token punctuation">)</span> <span class="token operator">!=</span> <span class="token punctuation">(</span>5px<span class="token punctuation">,</span> 7px<span class="token punctuation">,</span> 10px<span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token comment">// true</span>
<span class="token keyword">@debug</span> <span class="token punctuation">(</span>5px 7px 10px<span class="token punctuation">)</span> <span class="token operator">!=</span> [5px 7px 10px]<span class="token punctuation">;</span> <span class="token comment">// true</span>

<span class="token property"><span class="token variable">$theme</span></span><span class="token punctuation">:</span> <span class="token punctuation">(</span><span class="token string">&quot;venus&quot;</span><span class="token punctuation">:</span> #998099<span class="token punctuation">,</span> <span class="token string">&quot;nebula&quot;</span><span class="token punctuation">:</span> #d2e1dd<span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token keyword">@debug</span> <span class="token variable">$theme</span> <span class="token operator">==</span> <span class="token punctuation">(</span><span class="token string">&quot;venus&quot;</span><span class="token punctuation">:</span> #998099<span class="token punctuation">,</span> <span class="token string">&quot;nebula&quot;</span><span class="token punctuation">:</span> #d2e1dd<span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token comment">// true</span>
<span class="token keyword">@debug</span> <span class="token variable">$theme</span> <span class="token operator">!=</span> <span class="token punctuation">(</span><span class="token string">&quot;venus&quot;</span><span class="token punctuation">:</span> #998099<span class="token punctuation">,</span> <span class="token string">&quot;iron&quot;</span><span class="token punctuation">:</span> #dadbdf<span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token comment">// true</span>

<span class="token keyword">@debug</span> <span class="token boolean">true</span> <span class="token operator">==</span> <span class="token boolean">true</span><span class="token punctuation">;</span> <span class="token comment">// true</span>
<span class="token keyword">@debug</span> <span class="token boolean">true</span> <span class="token operator">!=</span> <span class="token boolean">false</span><span class="token punctuation">;</span> <span class="token comment">// true</span>
<span class="token keyword">@debug</span> <span class="token null keyword">null</span> <span class="token operator">!=</span> <span class="token boolean">false</span><span class="token punctuation">;</span> <span class="token comment">// true</span>

<span class="token keyword">@debug</span> <span class="token function">get-function</span><span class="token punctuation">(</span><span class="token string">&quot;rgba&quot;</span><span class="token punctuation">)</span> <span class="token operator">==</span> <span class="token function">get-function</span><span class="token punctuation">(</span><span class="token string">&quot;rgba&quot;</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token comment">// true</span>
<span class="token keyword">@debug</span> <span class="token function">get-function</span><span class="token punctuation">(</span><span class="token string">&quot;rgba&quot;</span><span class="token punctuation">)</span> <span class="token operator">!=</span> <span class="token function">get-function</span><span class="token punctuation">(</span><span class="token string">&quot;hsla&quot;</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token comment">// true</span>
</code></pre></div></div> <div role="tabpanel" aria-hidden="true" id="pane-null" aria-labelledby="tab-null" class="el-tab-pane" style="display:none;"><div class="language-sass extra-class"><pre class="language-sass"><code><span class="token atrule-line"><span class="token atrule">@debug</span> 1px <span class="token atrule">=</span><span class="token atrule">=</span> 1px  // true</span>
<span class="token atrule-line"><span class="token atrule">@debug</span> 1px !<span class="token atrule">=</span> 1em  // true</span>
<span class="token atrule-line"><span class="token atrule">@debug</span> 1 !<span class="token atrule">=</span> 1px  // true</span>
<span class="token atrule-line"><span class="token atrule">@debug</span> 96px <span class="token atrule">=</span><span class="token atrule">=</span> 1in  // true</span>

<span class="token atrule-line"><span class="token atrule">@debug</span> &quot;Helvetica&quot; <span class="token atrule">=</span><span class="token atrule">=</span> Helvetica  // true</span>
<span class="token atrule-line"><span class="token atrule">@debug</span> &quot;Helvetica&quot; !<span class="token atrule">=</span> &quot;Arial&quot;  // true</span>

<span class="token atrule-line"><span class="token atrule">@debug</span> hsl(34, 35%, 92.1%) <span class="token atrule">=</span><span class="token atrule">=</span> #f2ece4  // true</span>
<span class="token atrule-line"><span class="token atrule">@debug</span> rgba(179, 115, 153, 0.5) !<span class="token atrule">=</span> rgba(179, 115, 153, 0.8)  // true</span>

<span class="token atrule-line"><span class="token atrule">@debug</span> (5px 7px 10px) <span class="token atrule">=</span><span class="token atrule">=</span> (5px 7px 10px)  // true</span>
<span class="token atrule-line"><span class="token atrule">@debug</span> (5px 7px 10px) !<span class="token atrule">=</span> (10px 14px 20px)  // true</span>
<span class="token atrule-line"><span class="token atrule">@debug</span> (5px 7px 10px) !<span class="token atrule">=</span> (5px, 7px, 10px)  // true</span>
<span class="token atrule-line"><span class="token atrule">@debug</span> (5px 7px 10px) !<span class="token atrule">=</span> [5px 7px 10px]  // true</span>

<span class="token variable-line"><span class="token variable">$theme</span><span class="token punctuation">:</span> (</span><span class="token string">&quot;venus&quot;</span><span class="token selector">: #998099, </span><span class="token string">&quot;nebula&quot;</span><span class="token selector">: #d2e1dd) </span>
<span class="token atrule-line"><span class="token atrule">@debug</span> $theme <span class="token atrule">=</span><span class="token atrule">=</span> (&quot;venus&quot;: #998099, &quot;nebula&quot;: #d2e1dd)  // true</span>
<span class="token atrule-line"><span class="token atrule">@debug</span> $theme !<span class="token atrule">=</span> (&quot;venus&quot;: #998099, &quot;iron&quot;: #dadbdf)  // true</span>

<span class="token atrule-line"><span class="token atrule">@debug</span> true <span class="token atrule">=</span><span class="token atrule">=</span> true  // true</span>
<span class="token atrule-line"><span class="token atrule">@debug</span> true !<span class="token atrule">=</span> false  // true</span>
<span class="token atrule-line"><span class="token atrule">@debug</span> null !<span class="token atrule">=</span> false  // true</span>

<span class="token atrule-line"><span class="token atrule">@debug</span> get-function(&quot;rgba&quot;) <span class="token atrule">=</span><span class="token atrule">=</span> get-function(&quot;rgba&quot;)  // true</span>
<span class="token atrule-line"><span class="token atrule">@debug</span> get-function(&quot;rgba&quot;) !<span class="token atrule">=</span> get-function(&quot;hsla&quot;)  // true</span>
</code></pre></div></div></div></div></div> <footer class="page-edit"><!----> <div class="last-updated"><span class="prefix">上次更新: </span> <span class="time">11/5/2019, 4:49:11 PM</span></div></footer> <div class="page-nav"><p class="inner"><span class="prev">
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